Displays for electronic devices that detect and respond to the size and/or angular orientation of user input objects

ABSTRACT

An electronic device includes a touch-sensitive display screen including an array of electromagnetic radiation detectors. The array of electromagnetic radiation detectors is configured to generate an image signal that represents an image of a user input object that is closely spaced to the display, and to generate a touch signal in response to the display screen being touched by the user input object. The electronic device further includes a controller circuit that is configured to display a plurality of keys forming a keyboard and to display characters on the keys. The controller identifies from the image signal a size and/or an angular orientation of the user input object relative to the display screen. The controller identifies a user&#39;s selection among characters indicated on the keyboard keys in response to the identified size and/or the angular orientation of the user input object and in response to the touch signal, and outputs character data corresponding to the identified user selected character.

RELATED APPLICATION

This application is related to co-pending and commonly assigned U.S.application Ser. No. 12/250,108, entitled “User Input Displays ForMobile Devices,” filed Oct. 13, 2008, and to co-pending and commonlyassigned U.S. application Ser. No. 12/271,239, entitled “Displays forMobile Devices that Detect User Inputs Using Touch and Tracking of UserInput Objects,” filed Nov. 14, 2008 the disclosures of both of which areincorporated herein by reference in their entirety.

BACKGROUND

The present invention relates to displays for an electronic device, andin particular, to displays for receiving user input.

Various technologies are available to detect stylus and/or fingercontact in touch sensitive displays. For example, a resistivetouchscreen panel includes two spaced-apart, thin metallic electricallyconductive and resistive layers. When a user input object touches thepanel, the layers are connected, causing a change in an electricalcurrent. This change in electrical current is detected as a user inputcontact event. Resistive touchscreens are typically relatively precise,but may not be sufficiently sensitive, especially if the user's fingeris used to contact the touch screen.

A capacitive touchscreen is typically coated with a material, such asindium tin oxide, that conducts a continuous electrical current across asensor. The sensor exhibits a controlled field of stored electrons inboth horizontal and vertical axes to achieve a capacitance. When thesensor's capacitance field is altered by another capacitance field,e.g., a user's finger, electronic circuits located at each corner of thepanel measure the distortion and identify a location of the disturbance.Capacitive touch screens have a relatively high sensitivity, but theprecision with which the location of the event is detected can be low.

A side-optical touchscreen uses a grid of optical detectors on top ofthe surface of the display. Light is sent from one side to the other andreceived by detectors both horizontally and vertically. The beams oflight are broken when a finger or stylus is in close proximity such thatthe location can be translated into coordinates by the detectors.However, since the light sources and the detectors need to be placed ontop of the display, this configuration builds height that is generallynot desirable in mobile devices.

Another type of optical touchscreen uses the total internal reflectionprinciple. A refractive medium is filled with light, and when a fingeror other object is pressed against the surface, the internal reflectionlight path is interrupted, which results in light being reflectedoutside of the refractive medium. The light outside the refractivemedium can be detected by a camera. Refraction-optical touchscreensgenerally have good sensitivity and precision. However, the spacerequired for light sources and the refractive medium may increase thedimensions of the display and also limit the contrast of the displaybecause it is combined with a camera, and therefore, this type ofoptical touchscreen may not be practical for use with hand-held devices.

Moreover, touchscreens may not be able to operate using the same generalprotocols as a mouse-based user interface because user inputs may begenerated only upon contact with the screen. Thus, it may be moredifficult for a user to track movement of an icon, for example, toselect a region, than can be accomplished with a mouse. However, a mouseinput device may not be desirable to use with a compact, hand-helddevice.

SUMMARY

An electronic device according to some embodiments includes atouch-sensitive display screen including an array of electromagneticradiation detectors. The array of electromagnetic radiation detectors isconfigured to generate an image signal that represents an image of auser input object that is closely spaced to the display, and to generatea touch signal in response to the display screen being touched by theuser input object. The electronic device further includes a controllercircuit that is configured to display a plurality of keys forming akeyboard and to display characters on the keys. The controlleridentifies from the image signal a size and/or an angular orientation ofthe user input object relative to the display screen. The controlleridentifies a user's selection among characters indicated on the keyboardkeys in response to the identified size and/or the angular orientationof the user input object and in response to the touch signal, andoutputs character data corresponding to the identified user selectedcharacter.

In some further embodiments, the controller is further configured todisplay at least two different characters on each of a plurality of thekeyboard keys, and to identify a user's selection among the charactersdisplayed on a selected one of the multi-character keys in response tothe identified angular orientation of the user input object that isselecting the key.

In some further embodiments, the controller is further configured toidentify a first one of the multiple characters on the selected key thatoccurs in a direction indicated by the identified angular orientation ofthe user input object as being the user selected character.

In some further embodiments, the controller is further configured togenerate a selection signal that distinguishes between selection of oneof the keyboard keys by a left hand finger from selection by a righthand finger in response to the identified angular orientation of theuser object, to respond to the selection signal identifying that theselection is being made by a left hand finger by determining that theuser has selected a leftmost one of the multiple characters displayed onthe selected key, and to respond to the selection signal identifyingthat the selection is being made by a right hand finger by determiningthat the user has selected a rightmost one of the multiple charactersdisplayed on the selected key.

In some further embodiments, the controller is further configured togenerate a selection signal that distinguishes between selection amongthe keyboard keys by a finger on the user's left hand from selection byanother finger on the user's right hand in response to the identifiedangular orientation of the user input object, and is configured torespond to the selection signal indicating that a user is typing usingone hand by activating a predictive text entry operation that selects acandidate word among a database of defined words using a sequence ofuser selected keyboard characters.

In some further embodiments, the controller is further configured todisplay at least two different characters on each of a plurality of thekeyboard keys, and to identify a user's selection among the multiplecharacters displayed on a selected one of the keys in response to theidentified size of the user input object selecting the key.

In some further embodiments, the controller is further configured togenerate a selection signal that distinguishes between selection amongthe keyboard keys using the user's thumb from the selection usinganother non-thumb finger in response to the identified size of the userinput object.

In some further embodiments, the controller is further configured torespond to the selection signal identifying a selection by the user'sthumb by restricting the user's possible character selection to thedisplayed non-numeric characters, and to respond to the selection signalidentifying a selection by one of the user's non-thumb fingers byrestricting the user's possible character selection to the displayednon-alphabetic characters.

In some further embodiments, the controller is further configured torespond to the selection signal identifying the selection of a sequenceof the displayed alphabetic characters by one or both of the user'sthumbs by activating a predictive text entry operation that selects acandidate word among a database of defined words using the sequence ofselected alphabetic characters, and to discontinue the predictive textoperation in response to the selection signal identifying the selectionof at least one key by one of the user's non-thumb fingers.

In some further embodiments, the controller is further configured tomodify the displayed size of at least some of the keyboard keys inresponse to the identified size of the user input object.

In some further embodiments, the controller is further configured todisplay a first plurality of keys of a QWERTY keyboard on the displayscreen in response to identifying a first threshold size of the userinput object and to replace the displayed first plurality of keys with asecond plurality of keys of the QWERTY keyboard on the display screen inresponse to identifying a second threshold size of the user inputobject. The second threshold size is larger than the first thresholdsize and the second plurality of keys is less than the first pluralityof keys.

In some further embodiments, the controller is further configured togenerate a selection signal that distinguishes between selection of keysby the user's thumb from selection by one of the user's non-thumbfingers in response to the identified size, and is configured to enlargethe displayed size of at least one of the keyboard keys in response toidentifying selection by the user's thumb and to then decrease thedisplayed size of the previously enlarged at least one key in responseto identifying selection by one of the user's non-thumb fingers.

In some further embodiments, the controller is further configured togenerate a selection signal that distinguishes between selection of keysby the user's thumb from selection by one of the user's non-thumbfingers in response to the identified size of the user object, isconfigured to display a first plurality of alphabetic characters each ona different one of a first plurality of keys arranged in a QWERTYkeyboard configuration in response to identifying selection by one ofthe user's non-thumb fingers, and is configured to display groupings ofthe first plurality of alphabetic characters on a second plurality ofdisplayed keys, which is less than the first plurality of displayedkeys, in response to identifying selection by the user's thumb.

In some further embodiments, the controller is further configured todisplay the second plurality of displayed keys as larger key symbolsthan the first plurality of displayed keys.

In some further embodiments, the controller is further configured togenerate the selection signal to indicate whether selection of one ofthe keyboard keys is by a left hand finger or is by a right hand fingerin response to the identified angular orientation of the user object,and to replace the display of the first plurality of keys with thedisplay of the second plurality of keys in response to the selectionsignal identifying that the user is using fingers from both the rightand left hands to select among the first plurality of keys.

In some further embodiments, the controller is further configured toreplace the display of the first or second plurality of keys with thedisplay of a third plurality of keys in response to the selection signalidentifying that the user is selecting among the displayed keys usingone or the other thumbs, but not both, for at least a plural thresholdnumber of key selections.

In some further embodiments, the controller is further configured toreplace the display of the second plurality of keys with the display ofthe first plurality of keys in response to the selection signalidentifying that the user is selecting among the second plurality ofkeys using at least one of the user's non-thumb fingers.

In some further embodiments, the controller is further configured toreplace the display of the first plurality of keys with the display ofthe second plurality of keys in response to the selection signalidentifying that the user is selecting among the first plurality of keysusing both right and left hand thumbs within a threshold time, and toreplace the display of the second plurality of keys with the display ofthe first plurality of keys in response to the selection signalidentifying that the user is selecting among the second plurality ofkeys using at least one of the user's non-thumb fingers.

In some further embodiments, the controller is further configured torespond to the selection signal identifying a key selection by the lefthand finger by identifying the user's selection of a leftmost one of thecharacters displayed on the selected one of the second plurality ofkeys, and to respond to the selection signal identifying a selection bythe right hand finger by identifying the user's selection of a rightmostone of the characters displayed on the selected one of the secondplurality of keys.

In some other embodiments, an electronic device includes a touchsensitive display screen and a controller circuit. The touch-sensitivedisplay screen includes an array of electromagnetic radiation detectors,where the array of electromagnetic radiation detectors is configured togenerate an image signal that represents an image of a user input objectthat is closely spaced to the display, and to generate a touch signal inresponse to the display screen being touched by the user input object.The controller is configured to display on the display screen aplurality of keys forming a keyboard and to display characters on thekeys. The controller identifies from the image signal a size and/or anangular orientation of the user input object relative to the displayscreen. The controller identifies a user's selection among charactersindicated on the keyboard keys in response to the identified size and/oran angular orientation of the user input object and in response to thetouch signal, and outputs character data corresponding to the identifieduser selected character. The controller displays a first plurality ofalphabetic characters each on a different one of a first plurality ofkeys arranged in a QWERTY keyboard configuration in response toidentifying a first threshold size of the user input object, anddisplays groupings of the first plurality of alphabetic characters on asecond plurality of displayed keys in response to identifying a secondthreshold size of the user input object. The second threshold size islarger than the first threshold size and the second plurality of keys isless than the first plurality of keys. The controller distinguishesbetween selection of one of the keyboard keys by a left hand finger fromselection by a right hand finger in response to the identified angularorientation of the user object and identifies a first one of themultiple characters on the selected key that occurs in a directionindicated by the identified angular orientation of the user input objectas being the user selected character.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings, which are incorporated in and constitute a partof the specification, illustrate embodiments of the invention and,together with the description, serve to explain principles of theinvention:

FIG. 1 is a front view of a mobile communications device having adisplay according to embodiments of the present invention;

FIG. 2 is an exploded view of the display of FIG. 1;

FIG. 3 is a cross sectional view of the display of FIG. 1;

FIG. 4 is a cross sectional view of a layer of the display of FIG. 1including electromagnetic radiation emitters and detectors according toembodiments of the present invention;

FIG. 5A is a digital image of an electromagnetic radiation profileaccording to embodiments of the present invention;

FIG. 5B is an enhanced image derived from the image of FIG. 5A;

FIG. 5C is a schematic illustration of an identification of a user inputdevice using the images of FIGS. 5A-5B;

FIG. 5D is a schematic illustration of a target region identified basedon the illustration of FIG. 5C;

FIG. 6 is a flowchart illustrating operations according to embodimentsof the current invention;

FIG. 7 is a cross sectional view of a touch-sensitive display accordingto some embodiments of the present invention;

FIG. 8 is a cross sectional view of another touch-sensitive displayaccording to some embodiments of the present invention;

FIG. 9 is a flowchart illustrating operations according to embodimentsof the current invention;

FIG. 10 is a schematic block diagram illustrating a wirelesscommunication system with a wireless mobile communications deviceaccording to some embodiments of the invention;

FIG. 11 is a plan view of a display according to further embodiments;

FIG. 12 is a schematic illustration of a pixel of a display according tofurther embodiments;

FIG. 13 is a flowchart illustrating operations according to embodimentsof the current invention;

FIG. 14 illustrates digital images of user input objects according tovarious embodiments;

FIG. 15 illustrates some attributes of a hotspot that can be capturedand characterized according to some embodiments;

FIG. 16 illustrates an exemplary QWERTY keyboard that the controllercircuit may draw on the display device according to some embodiments;

FIG. 17 illustrates another exemplary keyboard that the controllercircuit may draw on the display device according to some embodiments;

FIG. 18 is a flowchart of operations that may be carried out by thecontroller to identify a user's selection among multiple characters thatare displayed on keyboard keys according to some embodiments;

FIG. 19 is a flowchart of operations that may be carried out by thecontroller to identify a user's selection among two characters that aredisplayed on a selected keyboard key according to some embodiments;

FIG. 20 is a flowchart of operations to may be carried out by thecontroller to activate and deactivate predictive text entry operationaccording to some embodiments;

FIG. 21 is a flowchart of operations to may be carried out by thecontroller to activate and deactivate predictive text entry operationand determine a user selection among numeric, alphabetic, and/or othercharacters that are displayed on a selected key in response to a size ofthe user's finger that selected the key according to some embodiments;

FIG. 22 illustrates an exemplary QWERTY keyboard that the controller maydisplay on the display device with one character per key according tosome embodiments;

FIG. 23 illustrates a more compact QWERTY keyboard that the controllermay display on the display device with two characters per key accordingto some embodiments;

FIG. 24 illustrates an still more compact keyboard that the controllermay display on the display device with two characters per key accordingto some embodiments;

FIG. 25 is a flowchart of exemplary operations that may be carried outby the controller to perform at least some functionality to control thenumber and size of keyboard keys and the number of characters aredisplayed on each key in response to whether the user has selected a keywith a non-thumb finger or a thumb according to some embodiments; and

FIG. 26 is a flowchart of exemplary operations that may be carried outby the controller to perform at least some functionality to control thenumber and size of keyboard keys and the number of characters aredisplayed on each key in response to whether the user is typing withthumb/non-thumb fingers and whether the user is typing using both handsaccording to some embodiments.

DETAILED DESCRIPTION

The present invention now will be described hereinafter with referenceto the accompanying drawings and examples, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Like numbers refer to like elements throughout. In the figures, thethickness of certain lines, layers, components, elements or features maybe exaggerated for clarity.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, steps, operations, elements, components, and/or groupsthereof. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items. As usedherein, phrases such as “between X and Y” and “between about X and Y”should be interpreted to include X and Y. As used herein, phrases suchas “between about X and Y” mean “between about X and about Y.” As usedherein, phrases such as “from about X to Y” mean “from about X to aboutY.”

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andrelevant art and should not be interpreted in an idealized or overlyformal sense unless expressly so defined herein. Well-known functions orconstructions may not be described in detail for brevity and/or clarity.

It will be understood that when an element is referred to as being “on,”“attached” to, “connected” to, “coupled” with, “contacting,” etc.,another element, it can be directly on, attached to, connected to,coupled with or contacting the other element or intervening elements mayalso be present. In contrast, when an element is referred to as being,for example, “directly on,” “directly attached” to, “directly connected”to, “directly coupled” with or “directly contacting” another element,there are no intervening elements present. It will also be appreciatedby those of skill in the art that references to a structure or featurethat is disposed “adjacent” another feature may have portions thatoverlap or underlie the adjacent feature.

Spatially relative terms, such as “under,” “below,” “lower,” “over,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is inverted, elements described as “under” or “beneath” otherelements or features would then be oriented “over” the other elements orfeatures. Thus, the exemplary term “under” can encompass both anorientation of “over” and “under.” The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Similarly, the terms“upwardly,” “downwardly,” “vertical,” “horizontal” and the like are usedherein for the purpose of explanation only unless specifically indicatedotherwise.

It will be understood that, although the terms “first,” “second,” etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. Thus, a “first” element discussed below couldalso be termed a “second” element without departing from the teachingsof the present invention. The sequence of operations (or steps) is notlimited to the order presented in the claims or figures unlessspecifically indicated otherwise.

As used herein, a “mobile communication terminal” or “terminal”includes, but is not limited to, a communication device that isconfigured to receive communication signals via a wireless interfacefrom, for example, a cellular network, a Wide Area Network, wirelesslocal area network (WLAN), a GPS system, and/or another RF communicationdevice.

As used herein, a “display” includes, but is not limited to, a devicecapable of providing a visual representation, such as graphics, lightingor back-lighting for displaying information and/or for aestheticpurposes.

As illustrated in FIGS. 1-3, an exemplary hand-held mobile electronicdevice 10 includes a liquid crystal diode (LCD) display 12. The display12 includes a backlighting layer 14, a liquid crystal layer 16, aprotective layer 18 (such as glass) and a touch panel layer 20. Asillustrated in FIG. 4, an alternative configuration employing organiclight emitting diodes (OLEDs) can be used in which the backlightinglayer 14 and/or the liquid crystal layer 16 are omitted. The display 12of FIG. 4 includes an array of electromagnetic radiation emitters E andelectromagnetic radiation detectors D on a substrate S. In someembodiments, the electromagnetic radiation emitters E andelectromagnetic radiation detectors D may include infrared emitters anddetectors, respectively. The substrate S also includes light emitters R,G and B, such as light emitting diodes (LEDs) or OLEDs, that are used todisplay pixels of various colors on the display 12.

As shown in FIG. 3, the emitters emit electromagnetic radiation ER awayfrom the display 12. If a user input object 22, such as a finger, ispositioned adjacent to (although not necessarily in contact with) thedisplay 12, then the electromagnetic radiation ER is reflected in adirection toward the display 12. The reflected electromagnetic radiationER can be detected by the detectors D within and/or beneath the liquidcrystal layer 16. Contact between the user input object 22 and thedisplay is not required, and the electromagnetic radiation ER can bereflected by the object 22 when the object 22 is spaced apart from thedisplay 12.

As illustrated in FIGS. 5A-5D and FIG. 6, the outputs of theelectromagnetic radiation detector D can be used to generate a twodimensional image in response to the detected electromagnetic radiationprofile (FIG. 5A; Block 100, FIG. 6), which can be used to identify auser input, such as a region of the display that is selected orhighlighted by the user (FIG. 5D; Block 102, FIG. 6). In thisconfiguration, a user input object, such as a finger or stylus, can bedetected when the object is spaced apart and not in physical contactwith the display 12.

For example, as shown in FIG. 5A, the data from the detectors D can beused to provide the image shown in FIG. 5A, which illustrates anexemplary infrared (IR) image of a user's finger. The contrast betweenthe pixels of the image can optionally be enhanced as shown in FIG. 5B.The shape of the user's finger F can then be identified as shown in FIG.5C. As shown in FIG. 5D, a target region T can then be identified, suchas by using image analysis techniques known to those of skill in the artto identify a region from the shape of the finger F (e.g., the tip ofthe finger F). In some embodiments, the target region T may be indicatedon the display 12 of FIGS. 1-4, e.g., by displaying an icon in thetarget region T. Thus, movement of the user input object or finger F canbe tracked on the display 12 by displaying the icon responsive tomovement of the finger F. In this configuration, various user inputs canbe registered by the display without contact from the finger F.

In particular embodiments, the display 12 can further include atouch-sensitive display such that additional user inputs can be detectedwhen a user input object contacts the display. In this configuration,user inputs to the display 12 may be used that are similar to those usedin a conventional mouse environment. An icon, such as a traditionalmouse arrow, can be moved when the user moves a user input objectwithout contacting the display 12, such as is described with respect toFIGS. 5A-5D. When the user touches the display 12, another user inputcan be received by the electronic device 10 that may be analogous toselecting or “clicking” a mouse button at a particular location.Accordingly, the display 12 can detect motion and/or contact of a userinput object to provide a user interface that is similar to atraditional mouse environment.

Although embodiments according to the present invention are describedwith respect to the infrared electromagnetic radiation emitters E andinfrared electromagnetic radiation detectors D in FIG. 4, it should beunderstood that other suitable techniques can be used to provide anelectromagnetic radiation profile responsive to a location of a userinput object. For example, in some embodiments, the emitters E shown inFIG. 4 can be omitted, and the detectors D can be configured to detectan obstruction of background electromagnetic radiation responsive to aposition of a user input object. In some embodiments, theelectromagnetic radiation detectors D can be configured to detectthermal radiation, e.g., from a digit or finger of a user's hand, as aninfrared (IR) signal.

According to further embodiments of the present invention, atouch-sensitive display system can be provided. As illustrated in FIG.7, the display 12′ can include an array of electromagnetic radiationemitters E₁, E₂ electromagnetic radiation detectors D₁, D₂ and arefractive medium 30. In the absence of contact from a user inputobject, such as a finger F and as shown with respect to the emitter E₂and detector D₂, the emitter E₂ is configured to emit electromagneticradiation toward the refractive medium 30, and the total internalreflection of the refractive medium 30 reflects the electromagneticradiation towards the detector D₂. The total internal reflection of therefractive medium 30 is disturbed or changed by contact from the fingerF as shown with respect to the emitter E₁ and detector D₁ such that thedirection of reflected electromagnetic radiation is changed and thedetector D₁ detects a reduced amount of electromagnetic radiation. Therefractive medium 30 can be formed of any suitable material, includingtransparent and/or translucent plastic, elastomer materials, or glass.In some embodiments, the surface 30 s can include a reflective orpartially reflective coating. Thus, the presence of the finger F can bedetected by a reduction or elimination of the detected electromagneticradiation in detector D₁.

In some embodiments as shown in FIG. 8, the emitters E and detectors Dcan be provided on a substrate S together with light emitters R, G, Bfor red, green and blue light respectively. The light emitters R, G, Bcan be LEDs or OLEDs. Accordingly, the emitters E and/or detectors D canbe integrated in the display.

As illustrated in FIG. 9, the emitters E and detectors D can be used todetect an electromagnetic radiation profile of the display (Block 150),for example, by detecting an amount of electromagnetic radiationdetected by an array of detectors D on the display 12′. The refractivemedium of the display can be contacted (Block 152), and a resultingchange in the electromagnetic radiation profile can be detected (Block154). The contact region can be detected (Block 156), for example, basedon an identification of the area in which the detectors detect a reducedamount of the reflected light.

In particular embodiments, the configuration shown in FIGS. 7 and 8 caninclude additional emitters E and detectors D that are configured todetect a user input object that is not in contact with the display 12′as is described with respect to FIGS. 2-6. The surface of the refractivemedium 30 of FIGS. 7 and 8 can become reflective based on the incidentangle of the electromagnetic radiation emitted by an emitter E (e.g.,about 45 degrees for a plastic or glass and air interface). At otherangles, the surface of the refractive medium 30 can be transmissive.Accordingly, the incident angles of the emitters E on the refractivemedium 30 can be selected to provide both emitter E and detector D pairsthat are configured as described with respect to FIGS. 7 and 8 (i.e., todetect reflected electromagnetic radiation and disruptions thereof bycontact with the refractive medium 30) and emitters E that emit ortransmit electromagnetic radiation through the refractive medium 30 asdescribed with respect to FIGS. 2-6 (i.e., to detect user input objectsthat are spaced apart from the display 12, 12′).

FIG. 10 is a schematic block diagram of a wireless communication systemthat includes a wireless terminal 200, such as a mobile wirelesscommunications terminal, that receives wireless communication signalsfrom a cellular base station 202 and/or a wireless local network 216.The cellular base station 202 is connected to a MTSO 206, which, inturn, is connected to a PSTN 212, and a network 214 (e.g., Internet).The mobile terminal 200 may communicate with the wireless local network216 using a communication protocol that may include, but is not limitedto, 802.11a, 802.11b, 802.11e, 802.11g, 802.11i, and/or other wirelesslocal area network protocols. The wireless local network 216 may beconnected to the network 214.

In some embodiments of the invention, the mobile terminal 200 includes acontroller circuit 232, a cellular transceiver circuit 234, a memorycircuit 236, a timing circuit (clock) 238, a local network transceivercircuit 240, a speaker device 242, a microphone device 244, a displaydevice 246 and a keypad 248. The display 246 can incorporate theelements of the displays 12, 12′ discussed herein.

The memory 236 stores software that is executed by the controller 232,and may include one or more erasable programmable read-only memories(EPROM or Flash EPROM), battery backed random access memory (RAM),magnetic, optical, or other digital storage device, and may be separatefrom, or at least partially within, the controller 232. The controller232 may include more than one processor, such as, for example, a generalpurpose processor and a digital signal processor, which may be enclosedin a common package or separate and apart from one another.

In particular, the controller 232 may be configured to controloperations as described with respect to FIGS. 1-9, for example, byidentifying a user input from the electromagnetic radiation profiledetected by the detectors D of the display 12, 12′ and by determining auser's selection among items that are displayed on the display device246 responsive to the identified input.

The cellular transceiver 234 typically includes both a transmitter (TX)250 and a receiver (RX) 252 to allow two way communications, but thepresent invention is not limited to such devices and, as used herein, a“transceiver” may include only the receiver 252. The mobile terminal 200may thereby communicate with the base station 202 using radio frequencysignals, which may be communicated through an antenna 254. For example,the mobile terminal 200 may be configured to communicate via thecellular transceiver 234 using one or more cellular communicationprotocols such as, for example, Advanced Mobile Phone Service (AMPS),ANSI-136, Global Standard for Mobile (GSM) communication, General PacketRadio Service (GPRS), enhanced data rates for GSM evolution (EDGE), codedivision multiple access (CDMA), wideband-CDMA, CDMA2000, and UniversalMobile Telecommunications System (UMTS). Communication protocols as usedherein may specify the information communicated, the timing, thefrequency, the modulation, and/or the operations for setting-up and/ormaintaining a communication connection. In some embodiments, theantennas 228 and 254 may be a single antenna.

Further embodiments are illustrated in FIGS. 11 and 12. As showntherein, a display 12 may include a plurality of pixels 42, respectiveones of which may include OLED and/or LED emitters R, G, B and an IRdetector D. The outputs of the IR detectors D can be sampled to generatean image signal that represents a sensed image, such as the IR imageillustrated in FIG. 5A, of space proximate to the display 12. As notedabove, the IR image can be processed using conventional image processingtechniques to identify the presence of a user input object, such as auser's finger and/or a stylus. According to some embodiments, motionsand/or actions by the user input object can be interpreted by thecontroller 232 as corresponding to various types of inputs or commands.Because the array of detectors D can sense motion of the user inputobject before it touches the display 12, the mobile terminal 200 canrespond to other types of actions, or combinations of actions, besidestouches or tough-based gestures. According to some embodiments,non-touch based gestures combined with touch-based gestures can be usedto control operations of the mobile terminal 200.

Gesture interpretation according to some embodiments may be moreinvolved than gesture interpretation using a conventional touch-onlytouchpad. For example, FIG. 13 is a diagram illustrating gestureinterpretation according to some embodiments. Blocks in the diagram ofFIG. 13 may represent steps used in gesture interpretation by a mobileterminal 200 and may be implemented as functional modules in a softwareprogram executed by the controller 232 in the mobile terminal 200.

Referring to FIG. 13, gesture interpretation may include one or more ofimage acquisition (Block/module 302), image filtering and normalization(Block/module 304), shape identification (Block/module 306), hotspotdetection (Block/module 308), touch detection (Block/module 310) andgesture determination (Block/module 312).

Image acquisition (Block/module 302) may be performed by samplingoutputs of the IR detectors D and responsively generating an imagesignal that represents a two-dimensional electromagnetic image of theuser input object (e.g., a finger or stylus). The generated image signalmay be filtered and normalized (Block/module 304) to reduce noise,sharpen edges, highlight image features, or for other purposes. Shapeidentification (Block/module 306) uses pattern recognition to identifyshapes represented in the image signal. In general, pattern recognitionmay involve feature extraction, in which numeric or symbolic informationabout an image is computed. A classification or description schemeclassifies the extracted features. For example, features that can beextracted from the image represented by the image signal can includescale-invariant and/or rotation-invariant features of the image.Object/image recognition techniques are well known to those skilled inthe art and need not be described in detail herein.

Once a shape of a user input object, such as a user's finger, a stylustip, etc., has been identified in the image, the location of a “hotspot”of the user input object is identified (Block/module 308). “Hotspot”refers to a point on the user input object at which contact between theuser input object and the display screen 12 is expected, if the userwere to touch the display 12 with the user input object. That is, eventhough the user input object (e.g., finger, stylus, etc.) is not incontact with the display 12, the operation of the mobile terminal 200can be controlled in response to a location of the hotspot, as discussedin more detail below.

Hotspot determination can be performed using one or more heuristicand/or deterministic techniques. For example, a hotspot can bepredicted/located based on a determination that a particular identifieduser input object is a user's finger, a user's thumb, or a stylus orother artificial pointing device. Hotspot determination can also beperformed based on calibration data. For example, a preliminary hotspotcan be determined, and the user can then be asked to touch the screen.The location of the hotspot can then be adjusted based on a differencebetween the expected and actual locations of the touch on the screen.

Shape determination is illustrated in more detail in FIG. 14. As showntherein, shape determination can be used to determine attributes of auser input object 55, such as shape (e.g., index finger, thumb orstylus), orientation (left or right hand), and distance to screen, asdetermined by edge blur. For example, as shown in FIG. 14( d), a userinput object 55 that is held away from the screen can exhibit edgeblurring 55 a. The amount of edge blur can be interpreted as a measureof the distance of the user input object 55 from the display 12.

Referring to FIG. 14( a), a hotspot 60 is determined based on thelocation and orientation of the user input object 55. A hotspot 60 isshown in more detail in FIG. 15.

According to some embodiments, a mobile terminal 200 may include ahotspot detection module 308 that analyzes an image captured by thedetectors D of the display 12. The hotspot detection module can identifyand output various attributes of the hotspot, such as the shape (s),position (x,y), angular orientation (θ), radius (r), distance fromdisplay screen (z), and/or velocity vector (u,v,w). One or more gesturescan be inferred in response to these attributes. In some embodiments,one or more gestures can be inferred in response to these attributes incombination with a touch on the touchscreen display 12.

The shape (s) refers to the type of shape detected as a user inputobject by the hotspot detection module 308, such as a finger, thumb,stylus, etc.

The position (x,y) represents the center of the hotspot 60. It may bedetermined based on knowledge of the type of shape that is used as auser input object. Once the shape has been identified, the hotspotdetection module 308 can apply a heuristic or deterministic technique tolocate the center of the hotspot 60 based on the type of shape.Furthermore, in some embodiments, different shapes can be used as userinput objects to activate different functions in the mobile terminal200. For example, a thumb shape can be used to activate differentfunctionality than a finger shape in some embodiments. The hotspotcenter position defines the location on the display 12 that is activatedby a particular gesture.

The hotspot center position (x,y) can be calibrated by instructing theuser to touch a location on the display 12. The location may be anylocation on the display, or may be a predefined location, such as alocation indicated by a graphic icon. The location of the touch isdetected by the touchscreen function of the display 12, and the positionof the hotspot center (x,y) relative to the shape (s) is determined.

The angular orientation (θ) may represent the angle of a major axis ofthe user input object relative to the orientation of the display screen12. Knowing the angular orientation (θ) may permit more accurate hotspotdetermination. Furthermore, in some embodiments, different commands maybe invoked based on the angular orientation of the user input object.

The size of the hotspot 60 is represented by the radius (r) of thehotspot 60. The radius represents the size of the portion of the userinput object that is in contact with the display 12. For example, afinger may have a larger contact radius with the display screen 12 thana stylus. The radius of the hotspot 60 may be used to determine theactivation area of effect of a gesture. In some embodiments, aprobabilistic model that takes the size of the hotspot into account canbe used to estimate or predict what area of the display screen 12 isbeing activated by the gesture.

The output (z) represents the distance of the user input object 55 tothe display screen 12. By tracking a distance of the user input objectto the display screen, gestures can be interpreted and used to invokecommands or actions in the mobile terminal 200 even if the user inputobject does not contact the display screen.

According to some embodiments, the distance (z) from the hotspot 60 tothe screen 12 can be estimated by analyzing the relative blurriness ofthe edges of a tracked object. That is, the distance (z) may beestimated as a function of both the type/shape of object being trackedas well as the blurriness of the tracked object. Distance of the userinput object from the display screen 12 can be used in some embodimentsto invoke an image zoom function.

The velocity vector (u,v,w) of the hotspot tracks the velocity of thehotspot in the x- and y-directions (u and v) as well as the z-direction(w). The velocity (u,v,w) of the hotspot can be determined bycalculating the distance covered from the last known hotspot coordinate.The velocity vector w in the z-direction can also take changes in thehotspot radius (r) into account when determining speed in thez-direction.

The display 12 also includes touchscreen capability, and the mobileterminal 200 is configured to determine when and where the screen 12 istouched by the user input object (Block/module 310). The display 12 mayinclude a conventional touchscreen (e.g., resistive, capacitive, etc.)and/or may be configured as described above with respect to theembodiments of FIGS. 7 and 8 to detect a touch by a user input object.

Gesture determination can be based on one or more of the hotspotattributes output by the hotspot detection module 308. For example, thegestures shown in Table 1 below can be identified based on one or morehotspot attributes. As shown in Table 1, a gesture can be identifiedbased on a pre-condition, a trigger, and a post condition. Thecombination of pre-condition, trigger, and post-condition signifies theoccurrence of an event, which can be mapped to a feature or function inthe mobile terminal 200. In Table 1, “HS” refers to “hotspot.” The“Event” column represents data that are passed from the gesturedetection to a higher layer (e.g. the application layer). Depending onthe gesture in question, different data may be available to theapplications. The number “1” in the Event column indicates that there isone event. The symbol “*” in the Event column indicates that there maybe multiple events while the gesture is detected.

TABLE 1 Possible Gesture Detection Algorithms Possible Post- Feature/Gesture Pre-condition Trigger condition Event Function Select HSdetected display HS detected Touch (x, y) w 1 Select touched Untouch (x,y) 1 Click HS detected display HS detected Touch (x, y) w 1 Select lessthan t_(click) touched and Untouch (x, y) 1 seconds ago w > w_(click)Drag HS detected + HS moved display (x, y)-[u, v, w]* Sort lists displaytouched touched Track HS detected HS moved HS detected (x,y)-[u, v, w]*Highlight items to be selected 2^(nd) Select HS detected + 2^(nd) HS HSdetected + Touch2 (x, y) 1 Option menu display detected display touchedtouched Flick HS detected + HS moved display not (x, y)-(u, v) 1 Scrolldisplay quickly touched touched Pinch two HS two HS one/two HS (x1, y1),(x2, y2)* Zoom in/out detected + separation detected + display distancedisplay touched changed touched Grab two HS display display not (x, y)Cut/copy detected + touched + two touched display not HS merge touchedDrop one HS display display not (x, y) Paste detected + touched + onetouched display not HS becomes touched two Sleep no HS Entire screen noHS Go to standby detected + covered with detected display not handtouched Wave no HS hand moved no HS (u, v) 1 Next/previous detected + infront of detected page (vertical display not screen from wave) touchedone side to Undo previous another action (horizontal wave) Answerdisplay not ear shape none (x, y) 1 Answer call touched detected

As can be seen from Table 1, three dimensional user input objecttracking and gesture interpretation is a superset of two dimensionalgesture interpretation that is familiar to users of touch pads and touchscreens. However, three dimensional user input object tracking andgesture interpretation enables a wider variety of gestures to beimplemented, including intuitive gestures, such as drag and drop.

Combining user input object tracking with algorithms to detect differentgestures enables the creation and implementation of a wide range ofunique user interface actions. For example, Table 1 defines both a“select” gesture as well as a “click” gesture. The “select” gesture isinterpreted in response to detection of a hotspot (the pre-condition),followed by detection of a touch on the display (the triggering event),followed by detection of the hotspot again (the post-condition). The“click” gesture is interpreted in response to detection of a touch onthe display with the velocity w in the z-direction exceeding a thresholdvelocity w_(click) (the triggering event), followed by detection of thehotspot again (the post-condition). Although these gestures can besimilar, these gestures can have different effects. For example, a“select” gesture can be used to slowly select a small portion of thedisplay screen, such as a hyperlink displayed on a web page, while the“click” gesture can be used to select a large hit area, such as aclickable button on the touchscreen.

The “tracking” gesture can provide better usability, for example inhighly dense web pages wherein the actual link can be highlighted aswith a mouse pointer, to give the user visual feedback of what portionof the display screen will be selected with a “select” gesture.

It will be appreciated that gestures can be different depending on theparticular user input object used and/or the same gesture can activatedifferent functions within the mobile terminal 200 depending on whichuser input object is used (e.g. finger versus thumb). Accordingly, itwill be appreciated that in some embodiments, shapes can be used totrigger different events. Furthermore, shapes can be used to increaseaccuracy of the selection of intended targets.

In accordance with some other embodiments, an electronic device includesa touch sensitive display and a controller circuit that is configured todetect the size and/or angular orientation of a user touch objectrelative to the display, and to use that information to assist withdetermining which characters that are visually displayed on a keyboardare being selected by the user and/or to modify how the keyboard andassociated characters are displayed to the user. These and furtherembodiments are described in detail below with regard to FIGS. 16-26.Although various embodiments are described herein in the context of themobile terminal 200 of FIG. 10, the invention is not limited thereto, asit may be embodied in any electronic device that includes a touchsensitive display screen and a controller circuit.

As used herein, the term “selected” refers to the image signalindicating that a finger or other user input object is closely locatedto, but not necessarily touching, a display, such as the touch sensitivedisplay 246. Accordingly, a user input object may be determined to haveselected a displayed key when it is adjacent to but not touching thekey. Thus, in accordance with some embodiments, a user input object maybe placed close to but not necessarily touching the display to triggerthe operation of various functionality described here, such as selectingcharacters on a displayed keyboard and/or causing different keyboardconfigurations to be displayed. Alternatively, in some otherembodiments, such functionality may not be triggered until the userinput object physically contacts one or more defined regions of thedisplay.

In some embodiments, as described above, the display device 246 includesan array of electromagnetic radiation detectors D that are configured togenerate an image signal that represents an image of a user input objectthat is closely spaced to the display. The user input object mayinclude, but is not limited to, fingers on the user's hand and/or astylus or other object manipulated by the user. The detectors D may befurther configured to generate a touch signal in response to the display246 being touched by the user input object.

The controller circuit 232 is configured to visually display on thedisplay device 246 a plurality of keys in an arrangement that forms akeyboard and to display characters on the keys. As used herein, the term“keyboard” includes, but is not limited to, a full or partial QWERTYkeyboard layout, a touchpad layout (e.g., conventional telephone keypadarrangement with alphabetic and numeric symbols), or any other keylayout. FIG. 16 illustrates an exemplary QWERTY keyboard that thecontroller circuit 232 may draw on the display device 246. Referring toFIG. 16, the QWERTY keyboard includes graphic symbols that representkeys 300 and characters that are displayed within the keys 300.

The controller 232 may be configured to identify from the image signal asize and/or an angular orientation of a closely spaced user input objectrelative to the display device 246. The controller 232 can identify auser's selection among the characters indicated on the keyboard keys 300in response to the identified size and/or angular orientation of theuser input object and in response to the touch signal, and outputcharacter data corresponding to the identified user selected characterto other circuitry/functional applications in the mobile terminal 200.

For example, when a touch point appears to be between two adjacent keys300, the controller 232 may identify a first one of the two keys thatoccurs in a direction indicated by the identified angular orientation ofthe user input object as being the user selected key. Thus, when afinger from the left hand touches the keyboard between two horizontallyadjacent keys, the controller 232 can respond thereto by determiningthat the left key was selected. Similarly, when a finger from the righthand touches the keyboard between the two horizontally adjacent keys,the controller 232 can respond thereto by determining that the right keywas selected.

Alternatively or additionally, the controller 232 may identify a user'sselection among a plurality of characters that are displayed on a selectkey in response to the size of the user's finger. For example, thecontroller 232 may distinguish between key selections that are made bythe user's thumb from selections made by the user's other non-thumbfingers (e.g., index finger). Accordingly, the angular orientationand/or the size of the user's finger can be used to identify which keyon a keyboard was selected and/or to identify which character wasselected among a plurality of characters that are displayed on aselected key. These and other embodiments are described in furtherdetail below.

The controller 232 may be configured to display a plurality of differentcharacters on some or all of the keyboard keys 300, and to identify auser's selection among the characters displayed on a selected one of themulti-character keys 300 in response to the identified angularorientation of the user input object that is selecting the key.

FIG. 17 illustrates an exemplary keyboard (e.g., keypad) that thecontroller 232 may draw on the display device 246. Referring to FIG. 16,the keyboard includes a plurality of characters that are displayed oneach key 310. The illustrated characters include alphabetic charactersand non-alphabetic characters (e.g., numbers, mathematical and othersymbols). The controller circuit 232 can be configured to identify auser's selection among the multiple characters displayed on a selectedone of the multi-character keys 310 in response to the identifiedangular orientation of the user input object that is selecting the key.

FIG. 18 is a flowchart of operations 320 that may be carried out by thecontroller 232 to identify a user's selection among multiple charactersthat are displayed on keyboard keys, such as on the keyboard 310 of FIG.17. Referring to FIGS. 17 and 18, the display 246 can generate (block322) an image signal representing an acquired image of a user inputobject before and/or after it contacts the display 246. The controller232 identifies (block 324) an angular orientation of the user inputobject indicated by the image signal relative to the display 246. Thecontroller 232 then identifies (block 326) a user selection among themultiple characters displayed on a selected key 310 in response to theidentified angular orientation, and outputs the user selected character(block 328).

For example, one of the keys 310 shown in FIG. 17 includes thealphabetic characters “a”, “b”, and “c”. The controller 232 can beconfigured to identify the leftmost character (“a”) as having beenselected by the user when the user's finger approaches the selected keyfrom the left, can identify the rightmost character (“c”) as having beenselected by the user when the user's finger approaches the selected keyfrom the right, and can identify the center character (“b”) as havingbeen selected by the user when the user's finger approaches the selectedkey from the top/bottom of the keyboard keys 310.

FIG. 19 is a flowchart of further operations 330 that may be carried outby the controller 232 to identify a user's selection among twocharacters that are displayed on keyboard keys, such as on the keyboard310 of FIG. 17. The operations 330 of FIG. 19 primarily differ from theoperations 320 of FIG. 18 in that the controller 232 can identifywhether the user has selected a key using a finger on the left hand oron the right-hand in response to the identified angular orientation, andcan select among two characters on the selected key in response thereto.

Referring to FIG. 19, the display 246 generates (block 332) an imagesignal representing an acquired image of a finger relative to a selectedkey. The controller 232 generates (block 334) a selection signal thatdistinguishes a key selection that has been made by a finger on the lefthand from a key selection that has been made by a finger on theright-hand. The controller 232 determines (block 336) whether a fingeron the user's left-hand selected the key and, if so, it outputs (block338) the left one of the two characters displayed on the selected key asthe user selected character. In contrast, if a finger on the user'sright-hand selected the key then the controller 232 outputs the rightcharacter displayed on the selected key as the user selected character.

Some further embodiments are directed to activating and deactivatingpredictive text entry operation in response to the angular orientationof the user input object relative to the display. The predictive textentry operation selects a candidate word among a database of definedwords using a sequence of alphabetic characters entered as a user typeson a keyboard that is displayed on a touch sensitive display.

FIG. 20 is a flowchart of operations 340 that may be carried out by thecontroller 232 to activate and deactivate predictive text entry.Referring to FIG. 20, the display 246 generates (block 342) an imagesignal representing an acquired image of a finger relative to a selectedkey. The controller 232 generates (block 344) a selection signal thatdistinguishes between selection among the keyboard keys by a finger onthe user's left-hand from selection by a finger on the user's right-handin response to identified angular orientation of the user input object.The controller 232 determines (block 346) from the selection signalwhether the user is typing with one hand and, if so, it activates (block348) a predictive text entry operation that selects the candidate wordamong a database to find words using a sequence of user selectedkeyboard characters as the user types on the keyboard using one hand.Alternatively, the controller 232 response to a determination (block346) that the user is typing on the keyboard using both hands bydeactivating (block 349) the predictive text entry operation.

Some further embodiments are directed to activating and deactivatingpredictive text entry operation and determining a user selection amongnumeric, alphabetic, and/or other characters that are displayed on aselected key in response to a size of the user's finger that selectedthe key. FIG. 21 is a flowchart of operations 350 to may be carried outby the controller 232 to perform at least some of this functionality.Referring to FIG. 21, the display 246 generates (block 352) an imagesignal representing an acquired image of a finger relative to a selectedkey. The controller 232 generates (block 354) a selection signal thatdistinguishes between the user using a thumb to select a key and using anon-thumb finger to select the key in response to the size of theselecting finger. The controller 232 determines (block 356) from theselection signal whether the user selected the key with a thumb and, ifso, it activates (block 358) a predictive text entry operation andrestricts (block 360) the user's possible character selections tonon-numeric characters among multiple display characters of the selectedkey. Alternatively, the controller 232 responds to a determination(block 356) that the user selected the key using a non-thumb finger byde-activating (block 362) a predictive text entry operation (if it wasactive) and restricting (block 364) the user's possible characterselections to numeric characters among multiple display characters ofthe selected key.

By way of a particular non-limiting example, referring to the keyboardkeys 310 shown in FIG. 17, the controller 232 can respond to a userselecting a key using a non-thumb finger (e.g., index finger) bydeactivating predictive text entry and restricting the user's possiblecharacter selections to the displayed non-alphabetic characters (e.g.,numbers and mathematic symbols) on the selected key. In contrast, thecontroller 232 can respond to a user selecting a key using a thumb byactivating predictive text entry and restricting the user's possiblecharacter selections to the displayed alphabetic characters on theselected key.

Some further embodiments are directed to controlling the number and/orsize of keyboard keys and/or the number of characters are displayed oneach key in response to a size of the user's finger and number offingers that the user uses to select keyboard keys. Exemplaryembodiments are described below with regard to FIGS. 22-26. FIG. 22illustrates an exemplary QWERTY keyboard 370 that the controller 232 maydisplay on the display device 246 with one character per key in responseto a user using a non-thumb finger (e.g. index finger) to type on thekeyboard. FIG. 23 illustrates a more compact QWERTY keyboard 380 thatthe controller 232 may display on the display device 246 with twocharacters per key in response to a user using two thumbs to type on thekeyboard 380. FIG. 24 illustrates an even more compact keyboard 390(e.g., a telephone keypad configuration) that the controller 232 maydisplay on the display device 246 with two characters per key inresponse to a user using two thumbs to type on the keyboard 380.

FIG. 25 is a flowchart of exemplary operations 400 that may be carriedout by the controller 232 to perform at least some functionality tocontrol the number and size of keyboard keys and the number ofcharacters are displayed on each key in response to whether the user hasselected a key with a non-thumb finger or a thumb. Referring to FIG. 25in combination with exemplary keyboard to FIGS. 22-23, the display 246generates (block 402) an image signal representing an acquired image ofa finger relative to a selected key. The controller 232 generates (block404) a selection signal that distinguishes between the user using athumb to select a key and using a non-thumb finger to select the key inresponse to the size of the selecting finger. The controller 232determines (block 406) from the selection signal whether the userselected the key with a non-thumb finger (e.g. index finger) and, if so,it displays (block 408) a first plurality of QWERTY keyboard keys 370with a different character on each key. When the controller 232determines (block 410) that the user selected a key using a thumb, itdisplays (block 412) a more compact QWERTY keyboard 380 having a smallernumber of keys but which are larger than the keys of keyboard 370. Thelarger keys of the keyboard 380 may be more accurately selected by auser who is using one or both thumbs to type on the keyboard 380. Thecontroller 232 may further activate predictive text entry operation(block 414) in response to the determination that the user is using athumb to type on the keyboard 380.

Accordingly, the controller 232 may display different keyboards to auser in response to whether the user is typing with thumbs or non-thumbfingers, where the different keyboards may be particularly configured tofacilitate easier more accurate typing by the user using the associatedthumbs/non-thumb fingers.

FIG. 26 is a flowchart of exemplary operations 420 that may be carriedout by the controller 232 to perform at least some functionality tocontrol the number and size of keyboard keys and the number ofcharacters are displayed on each key in response to whether the user istyping with thumb/non-thumb fingers and whether the user is typing usingboth hands. Referring to FIG. 26 in combination with exemplary keyboardto FIGS. 22-24, the display 246 generates (block 422) an image signalrepresenting an acquired image of a finger relative to a selected key.The controller 232 generates (block 424) a selection signal thatdistinguishes between the user typing with fingers on the left-hand fromtyping with fingers on the right hand in response to the identifiedangular orientation of the fingers relative to the display 246. Thecontroller 232 determines (block 426) from the selection signal whetherthe user is typing using non-thumb fingers (e.g., detects a definedlength sequence of non-thumb key selections) and, if so, it displays(block 428) a first plurality of QWERTY keyboard keys 370 with adifferent character on each key. When the controller 232 determines(block 430) that the user is typing using comes from both hands, itdisplays (block 432) a more compact QWERTY keyboard 380 having a smallernumber of keys but which are larger than the keys of keyboard 370. Thelarger keys of the keyboard 380 may be more accurately selected by theuser typing with both thumbs. Although not shown, the controller 232 mayfurther activate predictive text entry operation to predict words as theuser types with both thumbs on the keyboard 380. When the controller 232determines (block 434) that the user is typing using only one hand(e.g., one thumb on one hand), it displays (block 436) a yet morecompact keyboard 380 having a smaller number of keys but which arelarger than the keys of keyboard 370. The larger keys of the morecompact keyboard 380 may be more easily and accurately selected by theuser typing with one thumb. The controller 232 activates (block 438)predictive text entry operation to predict words as the user types onthe keyboard 390 using one hand.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although a few exemplary embodiments ofthis invention have been described, those skilled in the art willreadily appreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. Therefore, it is to be understood that the foregoing isillustrative of the present invention and is not to be construed aslimited to the specific embodiments disclosed, and that modifications tothe disclosed embodiments, as well as other embodiments, are intended tobe included within the scope of the appended claims. The invention isdefined by the following claims, with equivalents of the claims to beincluded therein.

1. An electronic device, comprising: a touch-sensitive display screenincluding an array of electromagnetic radiation detectors, wherein thearray of electromagnetic radiation detectors is configured to generatean image signal that represents an image of a user input object that isclosely spaced to the display, and to generate a touch signal inresponse to the display screen being touched by the user input object;and a controller circuit configured to display on the display screen aplurality of keys forming a keyboard and to display characters on thekeys, to identify from the image signal a size and/or an angularorientation of the user input object relative to the display screen, toidentify a user's selection among characters indicated on the keyboardkeys in response to the identified size and/or an angular orientation ofthe user input object and in response to the touch signal, and to outputcharacter data corresponding to the identified user selected character,wherein the controller circuit displays a first plurality of alphabeticcharacters each on a different one of a first plurality of keys arrangedin a QWERTY keyboard configuration in response to identifying a firstthreshold size of the user input object, and displays groupings of thefirst plurality of alphabetic characters on a second plurality ofdisplayed keys in response to identifying a second threshold size of theuser input object, wherein the second threshold size is larger than thefirst threshold size and the second plurality of keys is less than thefirst plurality of keys, and the controller circuit is furtherconfigured to distinguish between selection of one of the keyboard keysby a left hand finger from selection by a right hand finger in responseto the identified angular orientation of the user object and to identifya first one of the multiple characters on the selected key that occursin a direction indicated by the identified angular orientation of theuser input object as being the user selected character.
 2. A electronicdevice, comprising: a touch-sensitive display screen including an arrayof electromagnetic radiation detectors, wherein the array ofelectromagnetic radiation detectors is configured to generate an imagesignal that represents an image of a user input object that is closelyspaced to the display, and to generate a touch signal in response to thedisplay screen being touched by the user input object; and a controllercircuit configured to display on the display screen a plurality of keysforming a keyboard and to display characters on the keys, to identifyfrom the image signal a size and/or an angular orientation of the userinput object relative to the display screen, to identify a user'sselection among characters indicated on the keyboard keys in response tothe identified size and/or the angular orientation of the user inputobject and in response to the touch signal, and to output character datacorresponding to the identified user selected character.
 3. Theelectronic device of claim 2, wherein the controller circuit is furtherconfigured to identify a user's selection among the characters inresponse to the touch signal indicating a touch by the user input objectat a touch point between adjacent ones of the characters and in responseto the identified angular orientation of the user input object.
 4. Theelectronic device of claim 2, wherein the controller circuit is furtherconfigured to: display at least two different characters on each of aplurality of the keyboard keys, and to identify a user's selection amongthe characters displayed on a selected one of the multi-character keysin response to the identified angular orientation of the user inputobject that is selecting the key; and identify a first one of themultiple characters on the selected key that occurs in a directionindicated by the identified angular orientation of the user input objectas being the user selected character.
 5. The electronic device of claim2, wherein the controller circuit is further configured to: display atleast two different characters on each of a plurality of the keyboardkeys, and to identify a user's selection among the characters displayedon a selected one of the multi-character keys in response to theidentified angular orientation of the user input object that isselecting the key; and generate a selection signal that distinguishesbetween selection of one of the keyboard keys by a left hand finger fromselection by a right hand finger in response to the identified angularorientation of the user object, to respond to the selection signalidentifying that the selection is being made by a left hand finger bydetermining that the user has selected a leftmost one of the multiplecharacters displayed on the selected key, and to respond to theselection signal identifying that the selection is being made by a righthand finger by determining that the user has selected a rightmost one ofthe multiple characters displayed on the selected key.
 6. The electronicdevice of claim 2, wherein the controller circuit is further configuredto generate a selection signal that distinguishes between selectionamong the keyboard keys by a finger on the user's left hand fromselection by another finger on the user's right hand in response to theidentified angular orientation of the user input object, and isconfigured to respond to the selection signal indicating that a user istyping using one hand by activating a predictive text entry operationthat selects a candidate word among a database of defined words using asequence of user selected keyboard characters.
 7. The electronic deviceof claim 2, wherein the controller circuit is further configured todisplay at least two different characters on each of a plurality of thekeyboard keys, and to identify a user's selection among the multiplecharacters displayed on a selected one of the keys in response to theidentified size of the user input object selecting the key.
 8. Theelectronic device of claim 2, wherein the controller circuit is furtherconfigured to generate a selection signal that distinguishes betweenselection among the keyboard keys using the user's thumb from theselection using another non-thumb finger in response to the identifiedsize of the user input object.
 9. The electronic device of claim 8,wherein the controller circuit is further configured to respond to theselection signal identifying a selection by the user's thumb byrestricting the user's possible character selection to the displayednon-numeric characters, and to respond to the selection signalidentifying a selection by one of the user's non-thumb fingers byrestricting the user's possible character selection to the displayednon-alphabetic characters.
 10. The electronic device of claim 8, whereinthe controller circuit is further configured to respond to the selectionsignal identifying the selection of a sequence of the displayedalphabetic characters by one or both of the user's thumbs by activatinga predictive text entry operation that selects a candidate word among adatabase of defined words using the sequence of selected alphabeticcharacters, and to discontinue the predictive text operation in responseto the selection signal identifying the selection of at least one key byone of the user's non-thumb fingers.
 11. The electronic device of claim2, wherein the controller circuit is further configured to modify thedisplayed size of at least some of the keyboard keys in response to theidentified size of the user input object.
 12. The electronic device ofclaim 11, wherein the controller circuit is further configured todisplay a first plurality of keys of a QWERTY keyboard on the displayscreen in response to identifying a first threshold size of the userinput object and to replace the displayed first plurality of keys with asecond plurality of keys of the QWERTY keyboard on the display screen inresponse to identifying a second threshold size of the user inputobject, wherein the second threshold size is larger than the firstthreshold size and the second plurality of keys is less than the firstplurality of keys.
 13. The electronic device of claim 11, wherein thecontroller circuit is further configured to generate a selection signalthat distinguishes between selection of keys by the user's thumb fromselection by one of the user's non-thumb fingers in response to theidentified size, and is configured to enlarge the displayed size of atleast one of the keyboard keys in response to identifying selection bythe user's thumb and to then decrease the displayed size of thepreviously enlarged at least one key in response to identifyingselection by one of the user's non-thumb fingers.
 14. The electronicdevice of claim 11, wherein the controller circuit is further configuredto generate a selection signal that distinguishes between selection ofkeys by the user's thumb from selection by one of the user's non-thumbfingers in response to the identified size of the user object, isconfigured to display a first plurality of alphabetic characters each ona different one of a first plurality of keys arranged in a QWERTYkeyboard configuration in response to identifying selection by one ofthe user's non-thumb fingers, and is configured to display groupings ofthe first plurality of alphabetic characters on a second plurality ofdisplayed keys, which is less than the first plurality of displayedkeys, in response to identifying selection by the user's thumb.
 15. Theelectronic device of claim 14, wherein the controller circuit is furtherconfigured to display the second plurality of displayed keys as largerkey symbols than the first plurality of displayed keys.
 16. Theelectronic device of claim 14, wherein the controller circuit is furtherconfigured to generate the selection signal to indicate whetherselection of one of the keyboard keys is by a left hand finger or is bya right hand finger in response to the identified angular orientation ofthe user object, and to replace the display of the first plurality ofkeys with the display of the second plurality of keys in response to theselection signal identifying that the user is using fingers from boththe right and left hands to select among the first plurality of keys.17. The electronic device of claim 16, wherein the controller circuit isfurther configured to replace the display of the first or secondplurality of keys with the display of a third plurality of keys inresponse to the selection signal identifying that the user is selectingamong the displayed keys using one or the other thumbs, but not both,for at least a plural threshold number of key selections.
 18. Theelectronic device of claim 16, wherein the controller circuit is furtherconfigured to replace the display of the second plurality of keys withthe display of the first plurality of keys in response to the selectionsignal identifying that the user is selecting among the second pluralityof keys using at least one of the user's non-thumb fingers.
 19. Theelectronic device of claim 16, wherein the controller circuit is furtherconfigured to replace the display of the first plurality of keys withthe display of the second plurality of keys in response to the selectionsignal identifying that the user is selecting among the first pluralityof keys using both right and left hand thumbs within a threshold time,and to replace the display of the second plurality of keys with thedisplay of the first plurality of keys in response to the selectionsignal identifying that the user is selecting among the second pluralityof keys using at least one of the user's non-thumb fingers.
 20. Theelectronic device of claim 16, wherein the controller circuit is furtherconfigured to respond to the selection signal identifying a keyselection by the left hand finger by identifying the user's selection ofa leftmost one of the characters displayed on the selected one of thesecond plurality of keys, and to respond to the selection signalidentifying a selection by the right hand finger by identifying theuser's selection of a rightmost one of the characters displayed on theselected one of the second plurality of keys.